- PowerScore Staff
- Posts: 8916
- Joined: Feb 02, 2011
- Thu Jan 21, 2016 12:00 am
#34884
Complete Question Explanation
Main Point. The correct answer choice is (B)
The author opens this stimulus by introducing the claim that migrating birds may have some sort
of innate directional sense that allows them to find their way back to the same areas each year. The
author refutes this assertion, based on the lack of conclusive evidence that birds have such an innate
homing ability. The author goes on to provide the counter example of people who are able to find
their way home based on the use of landmarks; despite this ability, the author points out, no one
thinks that humans have a similar innate sense of direction. Birds, the author suggests, could be
using the same method.
Re-ordered and simplified, the argument breaks down as follows:
Premise: Some claim that migratory birds have an innate homing sense.
Premise: But they may just use landmarks, much like humans.
Conclusion: Thus, there is not much support for the belief that migratory birds have a
homing sense.
The question that follows asks for the author’s main conclusion. In this case, based on the lack of
conclusive evidence, the author concludes that there is little support for the argument that birds have
an innate sense of direction.
Answer choice (A): The author does not go so far as to claim that migratory birds have no innate
homing sense; rather, the author’s conclusion is that there is insufficient evidence to support this
assertion.
Answer choice (B): This is the correct answer choice. As discussed, the author's main conclusion
is that there is not much support for the claim that migratory birds have an innate homing sense.
Answer choice (C): The author does not mention inconclusive studies of migratory birds; while this
choice would support the author's conclusion, it is not the main point of the argument and should
thus be eliminated from contention.
Answer choice (D): The author introduces the use of landmarks as an approach the birds might take
if they do not actually have an innate homing sense. The author does not mention whether or not
such landmark use is an innate ability itself, so this cannot be the main point of the argument.
Answer choice (E): The author does not go so far as to say that birds definitely lack an innate
homing ability; rather, the conclusion is merely that there is insufficient evidence for the claim that
the birds have such an ability.
Main Point. The correct answer choice is (B)
The author opens this stimulus by introducing the claim that migrating birds may have some sort
of innate directional sense that allows them to find their way back to the same areas each year. The
author refutes this assertion, based on the lack of conclusive evidence that birds have such an innate
homing ability. The author goes on to provide the counter example of people who are able to find
their way home based on the use of landmarks; despite this ability, the author points out, no one
thinks that humans have a similar innate sense of direction. Birds, the author suggests, could be
using the same method.
Re-ordered and simplified, the argument breaks down as follows:
Premise: Some claim that migratory birds have an innate homing sense. Premise: But they may just use landmarks, much like humans. Conclusion: Thus, there is not much support for the belief that migratory birds have a homing sense.The question that follows asks for the author’s main conclusion. In this case, based on the lack of
conclusive evidence, the author concludes that there is little support for the argument that birds have
an innate sense of direction.
Answer choice (A): The author does not go so far as to claim that migratory birds have no innate
homing sense; rather, the author’s conclusion is that there is insufficient evidence to support this
assertion.
Answer choice (B): This is the correct answer choice. As discussed, the author's main conclusion
is that there is not much support for the claim that migratory birds have an innate homing sense.
Answer choice (C): The author does not mention inconclusive studies of migratory birds; while this
choice would support the author's conclusion, it is not the main point of the argument and should
thus be eliminated from contention.
Answer choice (D): The author introduces the use of landmarks as an approach the birds might take
if they do not actually have an innate homing sense. The author does not mention whether or not
such landmark use is an innate ability itself, so this cannot be the main point of the argument.
Answer choice (E): The author does not go so far as to say that birds definitely lack an innate
homing ability; rather, the conclusion is merely that there is insufficient evidence for the claim that
the birds have such an ability.